Merge pull request github#5545 from github/henrymercer/ql-pack-version-doc-update

CodeQL CLI Docs: Mention that QL packs use SemVer versioning

Author: henrymercer

docs/codeql/codeql-cli/about-ql-packs.rst

@@ -79,7 +79,7 @@ The following properties are supported in ``qlpack.yml`` files.
    * - ``version``
      - ``0.0.0``
      - All packs
-     - A version number for this QL pack. This field is not currently used by any commands, but may be required by future releases of CodeQL.
+     - A version number for this QL pack. This must be a valid semantic version that meets the `SemVer v2.0.0 specification <https://semver.org/spec/v2.0.0.html>`__.
    * - ``libraryPathDependencies``
      - ``codeql-javascript``
      - Optional